Aja Kona LH After Effects preview problem

We just bought our first AJA Kona LH cards to replace the Decklink boards in our Macs and now we are looking at a strange playback problem with After Effects preview on a broadcast monitor.

With the Decklink card everything was fine, but the Kona does not seem to be able to output a constant 25 fps on the broadcast monitor (we are working in a PAL environment). It seems to be going slower and faster (most of the time slower than 25 fps).

The preview output settings are set 625/25i and the funny thing is, the "mirror" preview on the mac's screen is stutter free and looks absolutely perfect.

Did I miss a special setting in After Effects or in Kona's control panel?

We are using latest generation Mac Pros with OSX 10.4.11
The machine in question doesn't even have a raid installed instead it runs with a 320GB internal SATA drive.
Yet, whenever I set the video preview output to the AJA Kona card it only renders with 11 fps (never faster, never slower, always exactly 11 fps) and once I switch it back to "computer display only" I end up with real time rendering.

Also the Kona Desktop feature does not work as I thought it would. The refresh rate on the broadcast screen attached to the Kona card seems to be extremly slow with OSX and Kona Desktop, the mouse does not move smoothly on the attaced broadcast monitor.

There is an installation of Final Cut Studio 1 on that machine, could that be a problem? (I would not know why, but you never know...)

The Studio I work at is having the same problem right now. We have 5 Mac Pros all with the Kona card, They all work great with Final Cut and out Ref monitors, but the min we just into AE (CS3) our Ram Previews do not play back at full frame rate. In fact, the playback speed is different on all the computers. I think the more complex the comp is the slower the play back may be. But im not sure. We had 2 pretty simple comps and one got a frame rate of 20fps and the other got 2fps, these are identical machines. 3.0 8Core Mac Pros, with 8GB of ram each. I just got off the phone with AJA and they said they would call me back they had to go talk to Engineering. So i will give an update, but if you have a solution please let me know.